I try to find the best quality sites for all kinds. Here's my favourite one for UFC atm. Watch the full video with one screen. No dodgy pop-ups, spoilers or malicious software as far as I can tell on his site (although I do use a vpn).
UFC Fight Night 143: CEJUDO VS. DILLASHAW - Прямая трансляция
http://wsenet.ru/blog/1228-cejudo-dillashaw.html
NOTE: ALWAYS use vpn when downloading or streaming.
Other fights:
Ramos vs Nurmagamedov https://ok.ru/video/898534804191
Rogerio Bontorin vs Magomed Bibulatov https://ok.ru/video/898539588319
OTHER CHAMPIONSHIPS:
Professional Fighting (PFL11) Championships : Magomed Magomedkerimov - Ray Cooper III https://ok.ru/video/1097863662133 (in Russian)